Hello Uday!
Generally, VIT takes admission on the basis of ranks. So, there is no official release of marks cutoffs or qualifying marks by VIT. Usually if your rank lies below 10000, you can have a good seat in VIT main campus. As per various estimation, top 500 ranks can be gained by obtaining 115 or more marks and less than 31 lies in the range of 20000 or below marks. But again, this is just an estimation of marks vs ranks. Hope the answer helps.
All the best!